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821.
Critical Flicker Fusion Thresholds (CFFTs) were measured in 644 elderly people identified from community-based general practice
records, and the relationship of CFFT with age was investigated. The CFFT was measured using the method of limits with mean
scores for three ascending (flicker/fusion) and three descending (fusion/flicker) presentations being recorded. The difference
between the ascending and descending means was found to be significantly correlated with age (r=−0.131,P<0.001) and may reflect a reduced sensitivity of the Central Nervous System to suprathreshold flicker with increasing age.
The results suggest that CFFT measurement has an important role to play in gerontological research as an objective measure
of cognitive aspects of the ageing process. 相似文献
822.
823.
D M Fragaszy S R Mitchell 《Journal of comparative psychology (Washington, D.C. : 1983)》1990,104(3):275-282
Patterns of manual preference and the extent to which preference provided a benefit in performance (movement time) were evaluated in 7 young adult capuchin monkeys (Cebus apella). Directions of preference were inconsistent within individual animals across home-cage activities, unimanual, and bimanual experimental tasks. Preferences were more strongly expressed in the experimental tasks than in the home cage. A left bias in the population for prehension, predicted by recent theories, was not evident in any setting. Movement time was moderately negatively correlated with degree of preference within experimental tasks. The benefit to performance conferred by lateral preference was not dependent on whether the right or left hand was preferred. Lateralization of prehension appears to be a flexible process in these monkeys, which can result in quickly realized benefits in some conditions. 相似文献
824.
M.A.S. Abdel Haleem 《Islam & Christian-Muslim Relations》1990,1(2):171-191
The story of Joseph in the Qur'an has been approached by many non‐Muslim writers1 who were content to list which details of the biblical story have been missed out from the biblical story and which points have been added, maintaining that these had their origins in biblical or other Jewish sources. Our treatment here concentrates on the texts of the story in the Qur'an and the Old Testament, attempting to identify the differing functions and preoccupations of the two accounts in their respective contexts, to show how this difference affects the choice of material and the treatment given to it. This article concludes that the two versions should be approached by readers, Muslims and non‐Muslims, with this difference in mind in order to appreciate the message and the qualities of each. 相似文献
825.
K. Blokker S. Bruin J. Bryden I. Houseman C. Okkerse C. Van der Meer A. P. Verkaik 《Knowledge, Technology, and Policy》1990,3(3):76-83
In this article the perspective shifts to the “upstream” end of the agricultural knowledge and information system (AKIS).
Because knowledge policy and strategic decision-making are not the prerogative of the public sector, organizations such as
cooperative unions and multinational companies are included. After considering the influence of the changing environment on
the nature of the AKIS, the role of knowledge management and policy in the emerging knowledge and information market is examined.
Special attention is given to public and private R&D. The article then looks where information technology (IT) fits in and
what considerations determine strategic investment in IT projects and sustained services. Some of the European experiences
with this strategic investment are evaluated. 相似文献
826.
827.
828.
Depression in some patients with spinal cord injuries may be clinically significant and, when present, should be treated to
decrease morbidity including decreased physical functioning. Depression associated with spinal cord injury (SCI) may be misevaluated,
due to (1) nonspecific multifactorial production of depression symptoms and (2) SCI-specific decrease in somatic sensory central
nervous system input. The Somatic Suppression Hypothesis suggests that SCI patients have difficulty experiencing any intense
emotion because of suppression of physiological arousal. In addition, cognitive processes that may reduce depression in SCI
patients include: (1) attribution of somatic symptoms of depression to medical (biological) causes, (2) realistic, positive
expectations for physical improvement, and (3) the perception that the disability of the SCI is only minimally related to
the patient’s self-care after complete evaluation. Health personnel should accept lack of depression in SCI, and should encourage
positive realistic expectations of recovery. 相似文献
829.
830.
Glenn SS 《The Behavior analyst / MABA》1993,16(2):133-151
Behavior analysis is a cultural system of which the Association for Behavior Analysis is a component cultural system. As cultural systems, they are composed of interlocking behavioral contingencies that constitute their cultural practices. Critical to the survival of both cultural systems is the frequency of interaction with and the nature of the content of the behavioral contingencies composing those cultural practices. The strengths of behavior analysis as a cultural system include its disciplinary character and its worldwide community of scientists and practitioners; its ability to be integrated into a scientific worldview; its track record in providing effective solutions to problems of importance to society; and the high levels of intellect, competence, and commitment that are characteristic of its participants. Weaknesses of behavior analysis are its status as an academic orphan, its relatively small size and its underdeveloped professional identity, and a lack of sociopolitical sophistication among many of its members. Behavior analysis will need to maximize its strengths and mitigate its weaknesses if it is to take advantage of the many opportunities available for growth in the modern world. 相似文献